net/iucv/af_iucv.c

   1 /*
   2  *  linux/net/iucv/af_iucv.c
   3  *
   4  *  IUCV protocol stack for Linux on zSeries
   5  *
   6  *  Copyright 2006 IBM Corporation
   7  *
   8  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/list.h>
  14 #include <linux/errno.h>
  15 #include <linux/kernel.h>
  16 #include <linux/sched.h>
  17 #include <linux/slab.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/init.h>
  20 #include <linux/poll.h>
  21 #include <net/sock.h>
  22 #include <asm/ebcdic.h>
  23 #include <asm/cpcmd.h>
  24 #include <linux/kmod.h>
  25
  26 #include <net/iucv/iucv.h>
  27 #include <net/iucv/af_iucv.h>
  28
  29 #define CONFIG_IUCV_SOCK_DEBUG 1
  30
  31 #define IPRMDATA 0x80
  32 #define VERSION "1.0"
  33
  34 static char iucv_userid[80];
  35
  36 static struct proto_ops iucv_sock_ops;
  37
  38 static struct proto iucv_proto = {
  39         .name           = "AF_IUCV",
  40         .owner          = THIS_MODULE,
  41         .obj_size       = sizeof(struct iucv_sock),
  42 };
  43
  44 /* Call Back functions */
  45 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
  46 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
  47 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
  48 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
  49                                  u8 ipuser[16]);
  50 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
  51
  52 static struct iucv_sock_list iucv_sk_list = {
  53         .lock = RW_LOCK_UNLOCKED,
  54         .autobind_name = ATOMIC_INIT(0)
  55 };
  56
  57 static struct iucv_handler af_iucv_handler = {
  58         .path_pending     = iucv_callback_connreq,
  59         .path_complete    = iucv_callback_connack,
  60         .path_severed     = iucv_callback_connrej,
  61         .message_pending  = iucv_callback_rx,
  62         .message_complete = iucv_callback_txdone
  63 };
  64
  65 static inline void high_nmcpy(unsigned char *dst, char *src)
  66 {
  67        memcpy(dst, src, 8);
  68 }
  69
  70 static inline void low_nmcpy(unsigned char *dst, char *src)
  71 {
  72        memcpy(&dst[8], src, 8);
  73 }
  74
  75 /* Timers */
  76 static void iucv_sock_timeout(unsigned long arg)
  77 {
  78         struct sock *sk = (struct sock *)arg;
  79
  80         bh_lock_sock(sk);
  81         sk->sk_err = ETIMEDOUT;
  82         sk->sk_state_change(sk);
  83         bh_unlock_sock(sk);
  84
  85         iucv_sock_kill(sk);
  86         sock_put(sk);
  87 }
  88
  89 static void iucv_sock_clear_timer(struct sock *sk)
  90 {
  91         sk_stop_timer(sk, &sk->sk_timer);
  92 }
  93
  94 static void iucv_sock_init_timer(struct sock *sk)
  95 {
  96         init_timer(&sk->sk_timer);
  97         sk->sk_timer.function = iucv_sock_timeout;
  98         sk->sk_timer.data = (unsigned long)sk;
  99 }
 100
 101 static struct sock *__iucv_get_sock_by_name(char *nm)
 102 {
 103         struct sock *sk;
 104         struct hlist_node *node;
 105
 106         sk_for_each(sk, node, &iucv_sk_list.head)
 107                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
 108                         return sk;
 109
 110         return NULL;
 111 }
 112
 113 static void iucv_sock_destruct(struct sock *sk)
 114 {
 115         skb_queue_purge(&sk->sk_receive_queue);
 116         skb_queue_purge(&sk->sk_write_queue);
 117 }
 118
 119 /* Cleanup Listen */
 120 static void iucv_sock_cleanup_listen(struct sock *parent)
 121 {
 122         struct sock *sk;
 123
 124         /* Close non-accepted connections */
 125         while ((sk = iucv_accept_dequeue(parent, NULL))) {
 126                 iucv_sock_close(sk);
 127                 iucv_sock_kill(sk);
 128         }
 129
 130         parent->sk_state = IUCV_CLOSED;
 131         sock_set_flag(parent, SOCK_ZAPPED);
 132 }
 133
 134 /* Kill socket */
 135 static void iucv_sock_kill(struct sock *sk)
 136 {
 137         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
 138                 return;
 139
 140         iucv_sock_unlink(&iucv_sk_list, sk);
 141         sock_set_flag(sk, SOCK_DEAD);
 142         sock_put(sk);
 143 }
 144
 145 /* Close an IUCV socket */
 146 static void iucv_sock_close(struct sock *sk)
 147 {
 148         unsigned char user_data[16];
 149         struct iucv_sock *iucv = iucv_sk(sk);
 150         int err;
 151         unsigned long timeo;
 152
 153         iucv_sock_clear_timer(sk);
 154         lock_sock(sk);
 155
 156         switch (sk->sk_state) {
 157         case IUCV_LISTEN:
 158                 iucv_sock_cleanup_listen(sk);
 159                 break;
 160
 161         case IUCV_CONNECTED:
 162         case IUCV_DISCONN:
 163                 err = 0;
 164
 165                 sk->sk_state = IUCV_CLOSING;
 166                 sk->sk_state_change(sk);
 167
 168                 if (!skb_queue_empty(&iucv->send_skb_q)) {
 169                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
 170                                 timeo = sk->sk_lingertime;
 171                         else
 172                                 timeo = IUCV_DISCONN_TIMEOUT;
 173                         err = iucv_sock_wait_state(sk, IUCV_CLOSED, 0, timeo);
 174                 }
 175
 176                 sk->sk_state = IUCV_CLOSED;
 177                 sk->sk_state_change(sk);
 178
 179                 if (iucv->path) {
 180                         low_nmcpy(user_data, iucv->src_name);
 181                         high_nmcpy(user_data, iucv->dst_name);
 182                         ASCEBC(user_data, sizeof(user_data));
 183                         err = iucv_path_sever(iucv->path, user_data);
 184                         iucv_path_free(iucv->path);
 185                         iucv->path = NULL;
 186                 }
 187
 188                 sk->sk_err = ECONNRESET;
 189                 sk->sk_state_change(sk);
 190
 191                 skb_queue_purge(&iucv->send_skb_q);
 192                 skb_queue_purge(&iucv->backlog_skb_q);
 193
 194                 sock_set_flag(sk, SOCK_ZAPPED);
 195                 break;
 196
 197         default:
 198                 sock_set_flag(sk, SOCK_ZAPPED);
 199                 break;
 200         }
 201
 202         release_sock(sk);
 203         iucv_sock_kill(sk);
 204 }
 205
 206 static void iucv_sock_init(struct sock *sk, struct sock *parent)
 207 {
 208         if (parent)
 209                 sk->sk_type = parent->sk_type;
 210 }
 211
 212 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
 213 {
 214         struct sock *sk;
 215
 216         sk = sk_alloc(PF_IUCV, prio, &iucv_proto, 1);
 217         if (!sk)
 218                 return NULL;
 219
 220         sock_init_data(sock, sk);
 221         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
 222         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
 223         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
 224         iucv_sk(sk)->send_tag = 0;
 225
 226         sk->sk_destruct = iucv_sock_destruct;
 227         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
 228         sk->sk_allocation = GFP_DMA;
 229
 230         sock_reset_flag(sk, SOCK_ZAPPED);
 231
 232         sk->sk_protocol = proto;
 233         sk->sk_state    = IUCV_OPEN;
 234
 235         iucv_sock_init_timer(sk);
 236
 237         iucv_sock_link(&iucv_sk_list, sk);
 238         return sk;
 239 }
 240
 241 /* Create an IUCV socket */
 242 static int iucv_sock_create(struct socket *sock, int protocol)
 243 {
 244         struct sock *sk;
 245
 246         if (sock->type != SOCK_STREAM)
 247                 return -ESOCKTNOSUPPORT;
 248
 249         sock->state = SS_UNCONNECTED;
 250         sock->ops = &iucv_sock_ops;
 251
 252         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
 253         if (!sk)
 254                 return -ENOMEM;
 255
 256         iucv_sock_init(sk, NULL);
 257
 258         return 0;
 259 }
 260
 261 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
 262 {
 263         write_lock_bh(&l->lock);
 264         sk_add_node(sk, &l->head);
 265         write_unlock_bh(&l->lock);
 266 }
 267
 268 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
 269 {
 270         write_lock_bh(&l->lock);
 271         sk_del_node_init(sk);
 272         write_unlock_bh(&l->lock);
 273 }
 274
 275 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
 276 {
 277         sock_hold(sk);
 278         list_add_tail(&iucv_sk(sk)->accept_q, &iucv_sk(parent)->accept_q);
 279         iucv_sk(sk)->parent = parent;
 280         parent->sk_ack_backlog++;
 281 }
 282
 283 void iucv_accept_unlink(struct sock *sk)
 284 {
 285         list_del_init(&iucv_sk(sk)->accept_q);
 286         iucv_sk(sk)->parent->sk_ack_backlog--;
 287         iucv_sk(sk)->parent = NULL;
 288         sock_put(sk);
 289 }
 290
 291 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
 292 {
 293         struct iucv_sock *isk, *n;
 294         struct sock *sk;
 295
 296         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 297                 sk = (struct sock *) isk;
 298                 lock_sock(sk);
 299
 300                 if (sk->sk_state == IUCV_CLOSED) {
 301                         release_sock(sk);
 302                         iucv_accept_unlink(sk);
 303                         continue;
 304                 }
 305
 306                 if (sk->sk_state == IUCV_CONNECTED ||
 307                     sk->sk_state == IUCV_SEVERED ||
 308                     !newsock) {
 309                         iucv_accept_unlink(sk);
 310                         if (newsock)
 311                                 sock_graft(sk, newsock);
 312
 313                         if (sk->sk_state == IUCV_SEVERED)
 314                                 sk->sk_state = IUCV_DISCONN;
 315
 316                         release_sock(sk);
 317                         return sk;
 318                 }
 319
 320                 release_sock(sk);
 321         }
 322         return NULL;
 323 }
 324
 325 int iucv_sock_wait_state(struct sock *sk, int state, int state2,
 326                          unsigned long timeo)
 327 {
 328         DECLARE_WAITQUEUE(wait, current);
 329         int err = 0;
 330
 331         add_wait_queue(sk->sk_sleep, &wait);
 332         while (sk->sk_state != state && sk->sk_state != state2) {
 333                 set_current_state(TASK_INTERRUPTIBLE);
 334
 335                 if (!timeo) {
 336                         err = -EAGAIN;
 337                         break;
 338                 }
 339
 340                 if (signal_pending(current)) {
 341                         err = sock_intr_errno(timeo);
 342                         break;
 343                 }
 344
 345                 release_sock(sk);
 346                 timeo = schedule_timeout(timeo);
 347                 lock_sock(sk);
 348
 349                 err = sock_error(sk);
 350                 if (err)
 351                         break;
 352         }
 353         set_current_state(TASK_RUNNING);
 354         remove_wait_queue(sk->sk_sleep, &wait);
 355         return err;
 356 }
 357
 358 /* Bind an unbound socket */
 359 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 360                           int addr_len)
 361 {
 362         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 363         struct sock *sk = sock->sk;
 364         struct iucv_sock *iucv;
 365         int err;
 366
 367         /* Verify the input sockaddr */
 368         if (!addr || addr->sa_family != AF_IUCV)
 369                 return -EINVAL;
 370
 371         lock_sock(sk);
 372         if (sk->sk_state != IUCV_OPEN) {
 373                 err = -EBADFD;
 374                 goto done;
 375         }
 376
 377         write_lock_bh(&iucv_sk_list.lock);
 378
 379         iucv = iucv_sk(sk);
 380         if (__iucv_get_sock_by_name(sa->siucv_name)) {
 381                 err = -EADDRINUSE;
 382                 goto done_unlock;
 383         }
 384         if (iucv->path) {
 385                 err = 0;
 386                 goto done_unlock;
 387         }
 388
 389         /* Bind the socket */
 390         memcpy(iucv->src_name, sa->siucv_name, 8);
 391
 392         /* Copy the user id */
 393         memcpy(iucv->src_user_id, iucv_userid, 8);
 394         sk->sk_state = IUCV_BOUND;
 395         err = 0;
 396
 397 done_unlock:
 398         /* Release the socket list lock */
 399         write_unlock_bh(&iucv_sk_list.lock);
 400 done:
 401         release_sock(sk);
 402         return err;
 403 }
 404
 405 /* Automatically bind an unbound socket */
 406 static int iucv_sock_autobind(struct sock *sk)
 407 {
 408         struct iucv_sock *iucv = iucv_sk(sk);
 409         char query_buffer[80];
 410         char name[12];
 411         int err = 0;
 412
 413         /* Set the userid and name */
 414         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
 415         if (unlikely(err))
 416                 return -EPROTO;
 417
 418         memcpy(iucv->src_user_id, query_buffer, 8);
 419
 420         write_lock_bh(&iucv_sk_list.lock);
 421
 422         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
 423         while (__iucv_get_sock_by_name(name)) {
 424                 sprintf(name, "%08x",
 425                         atomic_inc_return(&iucv_sk_list.autobind_name));
 426         }
 427
 428         write_unlock_bh(&iucv_sk_list.lock);
 429
 430         memcpy(&iucv->src_name, name, 8);
 431
 432         return err;
 433 }
 434
 435 /* Connect an unconnected socket */
 436 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
 437                              int alen, int flags)
 438 {
 439         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
 440         struct sock *sk = sock->sk;
 441         struct iucv_sock *iucv;
 442         unsigned char user_data[16];
 443         int err;
 444
 445         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
 446                 return -EINVAL;
 447
 448         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
 449                 return -EBADFD;
 450
 451         if (sk->sk_type != SOCK_STREAM)
 452                 return -EINVAL;
 453
 454         iucv = iucv_sk(sk);
 455
 456         if (sk->sk_state == IUCV_OPEN) {
 457                 err = iucv_sock_autobind(sk);
 458                 if (unlikely(err))
 459                         return err;
 460         }
 461
 462         lock_sock(sk);
 463
 464         /* Set the destination information */
 465         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
 466         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
 467
 468         high_nmcpy(user_data, sa->siucv_name);
 469         low_nmcpy(user_data, iucv_sk(sk)->src_name);
 470         ASCEBC(user_data, sizeof(user_data));
 471
 472         iucv = iucv_sk(sk);
 473         /* Create path. */
 474         iucv->path = iucv_path_alloc(IUCV_QUEUELEN_DEFAULT,
 475                                      IPRMDATA, GFP_KERNEL);
 476         err = iucv_path_connect(iucv->path, &af_iucv_handler,
 477                                 sa->siucv_user_id, NULL, user_data, sk);
 478         if (err) {
 479                 iucv_path_free(iucv->path);
 480                 iucv->path = NULL;
 481                 err = -ECONNREFUSED;
 482                 goto done;
 483         }
 484
 485         if (sk->sk_state != IUCV_CONNECTED) {
 486                 err = iucv_sock_wait_state(sk, IUCV_CONNECTED, IUCV_DISCONN,
 487                                 sock_sndtimeo(sk, flags & O_NONBLOCK));
 488         }
 489
 490         if (sk->sk_state == IUCV_DISCONN) {
 491                 release_sock(sk);
 492                 return -ECONNREFUSED;
 493         }
 494 done:
 495         release_sock(sk);
 496         return err;
 497 }
 498
 499 /* Move a socket into listening state. */
 500 static int iucv_sock_listen(struct socket *sock, int backlog)
 501 {
 502         struct sock *sk = sock->sk;
 503         int err;
 504
 505         lock_sock(sk);
 506
 507         err = -EINVAL;
 508         if (sk->sk_state != IUCV_BOUND || sock->type != SOCK_STREAM)
 509                 goto done;
 510
 511         sk->sk_max_ack_backlog = backlog;
 512         sk->sk_ack_backlog = 0;
 513         sk->sk_state = IUCV_LISTEN;
 514         err = 0;
 515
 516 done:
 517         release_sock(sk);
 518         return err;
 519 }
 520
 521 /* Accept a pending connection */
 522 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
 523                             int flags)
 524 {
 525         DECLARE_WAITQUEUE(wait, current);
 526         struct sock *sk = sock->sk, *nsk;
 527         long timeo;
 528         int err = 0;
 529
 530         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 531
 532         if (sk->sk_state != IUCV_LISTEN) {
 533                 err = -EBADFD;
 534                 goto done;
 535         }
 536
 537         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 538
 539         /* Wait for an incoming connection */
 540         add_wait_queue_exclusive(sk->sk_sleep, &wait);
 541         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
 542                 set_current_state(TASK_INTERRUPTIBLE);
 543                 if (!timeo) {
 544                         err = -EAGAIN;
 545                         break;
 546                 }
 547
 548                 release_sock(sk);
 549                 timeo = schedule_timeout(timeo);
 550                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 551
 552                 if (sk->sk_state != IUCV_LISTEN) {
 553                         err = -EBADFD;
 554                         break;
 555                 }
 556
 557                 if (signal_pending(current)) {
 558                         err = sock_intr_errno(timeo);
 559                         break;
 560                 }
 561         }
 562
 563         set_current_state(TASK_RUNNING);
 564         remove_wait_queue(sk->sk_sleep, &wait);
 565
 566         if (err)
 567                 goto done;
 568
 569         newsock->state = SS_CONNECTED;
 570
 571 done:
 572         release_sock(sk);
 573         return err;
 574 }
 575
 576 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
 577                              int *len, int peer)
 578 {
 579         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
 580         struct sock *sk = sock->sk;
 581
 582         addr->sa_family = AF_IUCV;
 583         *len = sizeof(struct sockaddr_iucv);
 584
 585         if (peer) {
 586                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
 587                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
 588         } else {
 589                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
 590                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
 591         }
 592         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
 593         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
 594         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
 595
 596         return 0;
 597 }
 598
 599 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 600                              struct msghdr *msg, size_t len)
 601 {
 602         struct sock *sk = sock->sk;
 603         struct iucv_sock *iucv = iucv_sk(sk);
 604         struct sk_buff *skb;
 605         struct iucv_message txmsg;
 606         int err;
 607
 608         err = sock_error(sk);
 609         if (err)
 610                 return err;
 611
 612         if (msg->msg_flags & MSG_OOB)
 613                 return -EOPNOTSUPP;
 614
 615         lock_sock(sk);
 616
 617         if (sk->sk_shutdown & SEND_SHUTDOWN) {
 618                 err = -EPIPE;
 619                 goto out;
 620         }
 621
 622         if (sk->sk_state == IUCV_CONNECTED) {
 623                 if (!(skb = sock_alloc_send_skb(sk, len,
 624                                                 msg->msg_flags & MSG_DONTWAIT,
 625                                                 &err)))
 626                         goto out;
 627
 628                 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 629                         err = -EFAULT;
 630                         goto fail;
 631                 }
 632
 633                 txmsg.class = 0;
 634                 txmsg.tag = iucv->send_tag++;
 635                 memcpy(skb->cb, &txmsg.tag, 4);
 636                 skb_queue_tail(&iucv->send_skb_q, skb);
 637                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
 638                                         (void *) skb->data, skb->len);
 639                 if (err) {
 640                         if (err == 3)
 641                                 printk(KERN_ERR "AF_IUCV msg limit exceeded\n");
 642                         skb_unlink(skb, &iucv->send_skb_q);
 643                         err = -EPIPE;
 644                         goto fail;
 645                 }
 646
 647         } else {
 648                 err = -ENOTCONN;
 649                 goto out;
 650         }
 651
 652         release_sock(sk);
 653         return len;
 654
 655 fail:
 656         kfree_skb(skb);
 657 out:
 658         release_sock(sk);
 659         return err;
 660 }
 661
 662 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 663                              struct msghdr *msg, size_t len, int flags)
 664 {
 665         int noblock = flags & MSG_DONTWAIT;
 666         struct sock *sk = sock->sk;
 667         struct iucv_sock *iucv = iucv_sk(sk);
 668         int target, copied = 0;
 669         struct sk_buff *skb, *rskb, *cskb;
 670         int err = 0;
 671
 672         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
 673                 skb_queue_empty(&iucv->backlog_skb_q) &&
 674                 skb_queue_empty(&sk->sk_receive_queue))
 675                 return 0;
 676
 677         if (flags & (MSG_OOB))
 678                 return -EOPNOTSUPP;
 679
 680         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 681
 682         skb = skb_recv_datagram(sk, flags, noblock, &err);
 683         if (!skb) {
 684                 if (sk->sk_shutdown & RCV_SHUTDOWN)
 685                         return 0;
 686                 return err;
 687         }
 688
 689         copied = min_t(unsigned int, skb->len, len);
 690
 691         cskb = skb;
 692         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
 693                 skb_queue_head(&sk->sk_receive_queue, skb);
 694                 if (copied == 0)
 695                         return -EFAULT;
 696                 goto done;
 697         }
 698
 699         len -= copied;
 700
 701         /* Mark read part of skb as used */
 702         if (!(flags & MSG_PEEK)) {
 703                 skb_pull(skb, copied);
 704
 705                 if (skb->len) {
 706                         skb_queue_head(&sk->sk_receive_queue, skb);
 707                         goto done;
 708                 }
 709
 710                 kfree_skb(skb);
 711
 712                 /* Queue backlog skbs */
 713                 rskb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
 714                 while (rskb) {
 715                         if (sock_queue_rcv_skb(sk, rskb)) {
 716                                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q,
 717                                                 rskb);
 718                                 break;
 719                         } else {
 720                                 rskb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
 721                         }
 722                 }
 723         } else
 724                 skb_queue_head(&sk->sk_receive_queue, skb);
 725
 726 done:
 727         return err ? : copied;
 728 }
 729
 730 static inline unsigned int iucv_accept_poll(struct sock *parent)
 731 {
 732         struct iucv_sock *isk, *n;
 733         struct sock *sk;
 734
 735         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
 736                 sk = (struct sock *) isk;
 737
 738                 if (sk->sk_state == IUCV_CONNECTED)
 739                         return POLLIN | POLLRDNORM;
 740         }
 741
 742         return 0;
 743 }
 744
 745 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
 746                             poll_table *wait)
 747 {
 748         struct sock *sk = sock->sk;
 749         unsigned int mask = 0;
 750
 751         poll_wait(file, sk->sk_sleep, wait);
 752
 753         if (sk->sk_state == IUCV_LISTEN)
 754                 return iucv_accept_poll(sk);
 755
 756         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
 757                 mask |= POLLERR;
 758
 759         if (sk->sk_shutdown & RCV_SHUTDOWN)
 760                 mask |= POLLRDHUP;
 761
 762         if (sk->sk_shutdown == SHUTDOWN_MASK)
 763                 mask |= POLLHUP;
 764
 765         if (!skb_queue_empty(&sk->sk_receive_queue) ||
 766             (sk->sk_shutdown & RCV_SHUTDOWN))
 767                 mask |= POLLIN | POLLRDNORM;
 768
 769         if (sk->sk_state == IUCV_CLOSED)
 770                 mask |= POLLHUP;
 771
 772         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
 773                 mask |= POLLIN;
 774
 775         if (sock_writeable(sk))
 776                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 777         else
 778                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 779
 780         return mask;
 781 }
 782
 783 static int iucv_sock_shutdown(struct socket *sock, int how)
 784 {
 785         struct sock *sk = sock->sk;
 786         struct iucv_sock *iucv = iucv_sk(sk);
 787         struct iucv_message txmsg;
 788         int err = 0;
 789         u8 prmmsg[8] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
 790
 791         how++;
 792
 793         if ((how & ~SHUTDOWN_MASK) || !how)
 794                 return -EINVAL;
 795
 796         lock_sock(sk);
 797         switch (sk->sk_state) {
 798         case IUCV_CLOSED:
 799                 err = -ENOTCONN;
 800                 goto fail;
 801
 802         default:
 803                 sk->sk_shutdown |= how;
 804                 break;
 805         }
 806
 807         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
 808                 txmsg.class = 0;
 809                 txmsg.tag = 0;
 810                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
 811                                         (void *) prmmsg, 8);
 812                 if (err) {
 813                         switch (err) {
 814                         case 1:
 815                                 err = -ENOTCONN;
 816                                 break;
 817                         case 2:
 818                                 err = -ECONNRESET;
 819                                 break;
 820                         default:
 821                                 err = -ENOTCONN;
 822                                 break;
 823                         }
 824                 }
 825         }
 826
 827         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
 828                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
 829                 if (err)
 830                         err = -ENOTCONN;
 831
 832                 skb_queue_purge(&sk->sk_receive_queue);
 833         }
 834
 835         /* Wake up anyone sleeping in poll */
 836         sk->sk_state_change(sk);
 837
 838 fail:
 839         release_sock(sk);
 840         return err;
 841 }
 842
 843 static int iucv_sock_release(struct socket *sock)
 844 {
 845         struct sock *sk = sock->sk;
 846         int err = 0;
 847
 848         if (!sk)
 849                 return 0;
 850
 851         iucv_sock_close(sk);
 852
 853         /* Unregister with IUCV base support */
 854         if (iucv_sk(sk)->path) {
 855                 iucv_path_sever(iucv_sk(sk)->path, NULL);
 856                 iucv_path_free(iucv_sk(sk)->path);
 857                 iucv_sk(sk)->path = NULL;
 858         }
 859
 860         sock_orphan(sk);
 861         iucv_sock_kill(sk);
 862         return err;
 863 }
 864
 865 /* Callback wrappers - called from iucv base support */
 866 static int iucv_callback_connreq(struct iucv_path *path,
 867                                  u8 ipvmid[8], u8 ipuser[16])
 868 {
 869         unsigned char user_data[16];
 870         unsigned char nuser_data[16];
 871         unsigned char src_name[8];
 872         struct hlist_node *node;
 873         struct sock *sk, *nsk;
 874         struct iucv_sock *iucv, *niucv;
 875         int err;
 876
 877         memcpy(src_name, ipuser, 8);
 878         EBCASC(src_name, 8);
 879         /* Find out if this path belongs to af_iucv. */
 880         read_lock(&iucv_sk_list.lock);
 881         iucv = NULL;
 882         sk_for_each(sk, node, &iucv_sk_list.head)
 883                 if (sk->sk_state == IUCV_LISTEN &&
 884                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
 885                         /*
 886                          * Found a listening socket with
 887                          * src_name == ipuser[0-7].
 888                          */
 889                         iucv = iucv_sk(sk);
 890                         break;
 891                 }
 892         read_unlock(&iucv_sk_list.lock);
 893         if (!iucv)
 894                 /* No socket found, not one of our paths. */
 895                 return -EINVAL;
 896
 897         bh_lock_sock(sk);
 898
 899         /* Check if parent socket is listening */
 900         low_nmcpy(user_data, iucv->src_name);
 901         high_nmcpy(user_data, iucv->dst_name);
 902         ASCEBC(user_data, sizeof(user_data));
 903         if (sk->sk_state != IUCV_LISTEN) {
 904                 err = iucv_path_sever(path, user_data);
 905                 goto fail;
 906         }
 907
 908         /* Check for backlog size */
 909         if (sk_acceptq_is_full(sk)) {
 910                 err = iucv_path_sever(path, user_data);
 911                 goto fail;
 912         }
 913
 914         /* Create the new socket */
 915         nsk = iucv_sock_alloc(NULL, SOCK_STREAM, GFP_ATOMIC);
 916         if (!nsk) {
 917                 err = iucv_path_sever(path, user_data);
 918                 goto fail;
 919         }
 920
 921         niucv = iucv_sk(nsk);
 922         iucv_sock_init(nsk, sk);
 923
 924         /* Set the new iucv_sock */
 925         memcpy(niucv->dst_name, ipuser + 8, 8);
 926         EBCASC(niucv->dst_name, 8);
 927         memcpy(niucv->dst_user_id, ipvmid, 8);
 928         memcpy(niucv->src_name, iucv->src_name, 8);
 929         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
 930         niucv->path = path;
 931
 932         /* Call iucv_accept */
 933         high_nmcpy(nuser_data, ipuser + 8);
 934         memcpy(nuser_data + 8, niucv->src_name, 8);
 935         ASCEBC(nuser_data + 8, 8);
 936
 937         path->msglim = IUCV_QUEUELEN_DEFAULT;
 938         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
 939         if (err) {
 940                 err = iucv_path_sever(path, user_data);
 941                 goto fail;
 942         }
 943
 944         iucv_accept_enqueue(sk, nsk);
 945
 946         /* Wake up accept */
 947         nsk->sk_state = IUCV_CONNECTED;
 948         sk->sk_data_ready(sk, 1);
 949         err = 0;
 950 fail:
 951         bh_unlock_sock(sk);
 952         return 0;
 953 }
 954
 955 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
 956 {
 957         struct sock *sk = path->private;
 958
 959         sk->sk_state = IUCV_CONNECTED;
 960         sk->sk_state_change(sk);
 961 }
 962
 963 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len,
 964                              struct sk_buff_head *fragmented_skb_q)
 965 {
 966         int dataleft, size, copied = 0;
 967         struct sk_buff *nskb;
 968
 969         dataleft = len;
 970         while (dataleft) {
 971                 if (dataleft >= sk->sk_rcvbuf / 4)
 972                         size = sk->sk_rcvbuf / 4;
 973                 else
 974                         size = dataleft;
 975
 976                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
 977                 if (!nskb)
 978                         return -ENOMEM;
 979
 980                 memcpy(nskb->data, skb->data + copied, size);
 981                 copied += size;
 982                 dataleft -= size;
 983
 984                 skb_reset_transport_header(nskb);
 985                 skb_reset_network_header(nskb);
 986                 nskb->len = size;
 987
 988                 skb_queue_tail(fragmented_skb_q, nskb);
 989         }
 990
 991         return 0;
 992 }
 993
 994 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
 995 {
 996         struct sock *sk = path->private;
 997         struct iucv_sock *iucv = iucv_sk(sk);
 998         struct sk_buff *skb, *fskb;
 999         struct sk_buff_head fragmented_skb_q;
1000         int rc;
1001
1002         skb_queue_head_init(&fragmented_skb_q);
1003
1004         if (sk->sk_shutdown & RCV_SHUTDOWN)
1005                 return;
1006
1007         skb = alloc_skb(msg->length, GFP_ATOMIC | GFP_DMA);
1008         if (!skb) {
1009                 iucv_path_sever(path, NULL);
1010                 return;
1011         }
1012
1013         if (msg->flags & IPRMDATA) {
1014                 skb->data = NULL;
1015                 skb->len = 0;
1016         } else {
1017                 rc = iucv_message_receive(path, msg, 0, skb->data,
1018                                           msg->length, NULL);
1019                 if (rc) {
1020                         kfree_skb(skb);
1021                         return;
1022                 }
1023                 if (skb->truesize >= sk->sk_rcvbuf / 4) {
1024                         rc = iucv_fragment_skb(sk, skb, msg->length,
1025                                                &fragmented_skb_q);
1026                         kfree_skb(skb);
1027                         skb = NULL;
1028                         if (rc) {
1029                                 iucv_path_sever(path, NULL);
1030                                 return;
1031                         }
1032                 } else {
1033                         skb_reset_transport_header(skb);
1034                         skb_reset_network_header(skb);
1035                         skb->len = msg->length;
1036                 }
1037         }
1038         /* Queue the fragmented skb */
1039         fskb = skb_dequeue(&fragmented_skb_q);
1040         while (fskb) {
1041                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1042                         skb_queue_tail(&iucv->backlog_skb_q, fskb);
1043                 else if (sock_queue_rcv_skb(sk, fskb))
1044                         skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, fskb);
1045                 fskb = skb_dequeue(&fragmented_skb_q);
1046         }
1047
1048         /* Queue the original skb if it exists (was not fragmented) */
1049         if (skb) {
1050                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1051                         skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1052                 else if (sock_queue_rcv_skb(sk, skb))
1053                         skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1054         }
1055
1056 }
1057
1058 static void iucv_callback_txdone(struct iucv_path *path,
1059                                  struct iucv_message *msg)
1060 {
1061         struct sock *sk = path->private;
1062         struct sk_buff *this;
1063         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1064         struct sk_buff *list_skb = list->next;
1065         unsigned long flags;
1066
1067         if (list_skb) {
1068                 spin_lock_irqsave(&list->lock, flags);
1069
1070                 do {
1071                         this = list_skb;
1072                         list_skb = list_skb->next;
1073                 } while (memcmp(&msg->tag, this->cb, 4) && list_skb);
1074
1075                 spin_unlock_irqrestore(&list->lock, flags);
1076
1077                 skb_unlink(this, &iucv_sk(sk)->send_skb_q);
1078                 kfree_skb(this);
1079         }
1080
1081         if (sk->sk_state == IUCV_CLOSING) {
1082                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1083                         sk->sk_state = IUCV_CLOSED;
1084                         sk->sk_state_change(sk);
1085                 }
1086         }
1087
1088 }
1089
1090 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1091 {
1092         struct sock *sk = path->private;
1093
1094         if (!list_empty(&iucv_sk(sk)->accept_q))
1095                 sk->sk_state = IUCV_SEVERED;
1096         else
1097                 sk->sk_state = IUCV_DISCONN;
1098
1099         sk->sk_state_change(sk);
1100 }
1101
1102 static struct proto_ops iucv_sock_ops = {
1103         .family         = PF_IUCV,
1104         .owner          = THIS_MODULE,
1105         .release        = iucv_sock_release,
1106         .bind           = iucv_sock_bind,
1107         .connect        = iucv_sock_connect,
1108         .listen         = iucv_sock_listen,
1109         .accept         = iucv_sock_accept,
1110         .getname        = iucv_sock_getname,
1111         .sendmsg        = iucv_sock_sendmsg,
1112         .recvmsg        = iucv_sock_recvmsg,
1113         .poll           = iucv_sock_poll,
1114         .ioctl          = sock_no_ioctl,
1115         .mmap           = sock_no_mmap,
1116         .socketpair     = sock_no_socketpair,
1117         .shutdown       = iucv_sock_shutdown,
1118         .setsockopt     = sock_no_setsockopt,
1119         .getsockopt     = sock_no_getsockopt
1120 };
1121
1122 static struct net_proto_family iucv_sock_family_ops = {
1123         .family = AF_IUCV,
1124         .owner  = THIS_MODULE,
1125         .create = iucv_sock_create,
1126 };
1127
1128 static int __init afiucv_init(void)
1129 {
1130         int err;
1131
1132         if (!MACHINE_IS_VM) {
1133                 printk(KERN_ERR "AF_IUCV connection needs VM as base\n");
1134                 err = -EPROTONOSUPPORT;
1135                 goto out;
1136         }
1137         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1138         if (unlikely(err)) {
1139                 printk(KERN_ERR "AF_IUCV needs the VM userid\n");
1140                 err = -EPROTONOSUPPORT;
1141                 goto out;
1142         }
1143
1144         err = iucv_register(&af_iucv_handler, 0);
1145         if (err)
1146                 goto out;
1147         err = proto_register(&iucv_proto, 0);
1148         if (err)
1149                 goto out_iucv;
1150         err = sock_register(&iucv_sock_family_ops);
1151         if (err)
1152                 goto out_proto;
1153         printk(KERN_INFO "AF_IUCV lowlevel driver initialized\n");
1154         return 0;
1155
1156 out_proto:
1157         proto_unregister(&iucv_proto);
1158 out_iucv:
1159         iucv_unregister(&af_iucv_handler, 0);
1160 out:
1161         return err;
1162 }
1163
1164 static void __exit afiucv_exit(void)
1165 {
1166         sock_unregister(PF_IUCV);
1167         proto_unregister(&iucv_proto);
1168         iucv_unregister(&af_iucv_handler, 0);
1169
1170         printk(KERN_INFO "AF_IUCV lowlevel driver unloaded\n");
1171 }
1172
1173 module_init(afiucv_init);
1174 module_exit(afiucv_exit);
1175
1176 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1177 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1178 MODULE_VERSION(VERSION);
1179 MODULE_LICENSE("GPL");
1180 MODULE_ALIAS_NETPROTO(PF_IUCV);